html-minimizer-webpack-plugin/dist/index.js

html minimizer plugin for Webpack

"use strict";

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.default = void 0;

var _os = _interopRequireDefault(require("os"));

var _schemaUtils = require("schema-utils");

var _serializeJavascript = _interopRequireDefault(require("serialize-javascript"));

var _pLimit = _interopRequireDefault(require("p-limit"));

var _jestWorker = _interopRequireDefault(require("jest-worker"));

var _options = _interopRequireDefault(require("./options.json"));

var _minify = require("./minify");

function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }

class HtmlMinimizerPlugin {
  constructor(options = {}) {
    (0, _schemaUtils.validate)(_options.default, options, {
      name: "Html Minimizer Plugin",
      baseDataPath: "options"
    });
    const {
      minify,
      minimizerOptions = {},
      test = /\.html(\?.*)?$/i,
      parallel = true,
      include,
      exclude
    } = options;
    this.options = {
      test,
      parallel,
      include,
      exclude,
      minify,
      minimizerOptions
    };
  }

  static buildError(error, file, context) {
    return new Error(`${file} in "${context}" from Html Minimizer\n${error.stack}`);
  }

  static getAvailableNumberOfCores(parallel) {
    // In some cases cpus() returns undefined
    // https://github.com/nodejs/node/issues/19022
    const cpus = _os.default.cpus() || {
      length: 1
    };
    return parallel === true ? cpus.length - 1 : Math.min(Number(parallel) || 0, cpus.length - 1);
  }

  async optimize(compiler, compilation, assets, optimizeOptions) {
    const cache = compilation.getCache("HtmlMinimizerWebpackPlugin");
    let numberOfAssetsForMinify = 0;
    const assetsForMinify = await Promise.all(Object.keys(assets).filter(name => {
      const {
        info
      } = compilation.getAsset(name); // Skip double minimize assets from child compilation

      if (info.minimized) {
        return false;
      }

      if (!compiler.webpack.ModuleFilenameHelpers.matchObject.bind( // eslint-disable-next-line no-undefined
      undefined, this.options)(name)) {
        return false;
      }

      return true;
    }).map(async name => {
      const {
        info,
        source
      } = compilation.getAsset(name);
      const eTag = cache.getLazyHashedEtag(source);
      const cacheItem = cache.getItemCache(name, eTag);
      const output = await cacheItem.getPromise();

      if (!output) {
        numberOfAssetsForMinify += 1;
      }

      return {
        name,
        info,
        inputSource: source,
        output,
        cacheItem
      };
    }));
    let getWorker;
    let initializedWorker;
    let numberOfWorkers;

    if (optimizeOptions.availableNumberOfCores > 0) {
      // Do not create unnecessary workers when the number of files is less than the available cores, it saves memory
      numberOfWorkers = Math.min(numberOfAssetsForMinify, optimizeOptions.availableNumberOfCores); // eslint-disable-next-line consistent-return

      getWorker = () => {
        if (initializedWorker) {
          return initializedWorker;
        }

        initializedWorker = new _jestWorker.default(require.resolve("./minify"), {
          numWorkers: numberOfWorkers,
          enableWorkerThreads: true
        }); // https://github.com/facebook/jest/issues/8872#issuecomment-524822081

        const workerStdout = initializedWorker.getStdout();

        if (workerStdout) {
          workerStdout.on("data", chunk => process.stdout.write(chunk));
        }

        const workerStderr = initializedWorker.getStderr();

        if (workerStderr) {
          workerStderr.on("data", chunk => process.stderr.write(chunk));
        }

        return initializedWorker;
      };
    }

    const limit = (0, _pLimit.default)(getWorker && numberOfAssetsForMinify > 0 ? numberOfWorkers : Infinity);
    const {
      RawSource
    } = compiler.webpack.sources;
    const scheduledTasks = [];

    for (const asset of assetsForMinify) {
      scheduledTasks.push(limit(async () => {
        const {
          name,
          inputSource,
          cacheItem
        } = asset;
        let {
          output
        } = asset;
        let input;
        const sourceFromInputSource = inputSource.source();

        if (!output) {
          input = sourceFromInputSource;

          if (Buffer.isBuffer(input)) {
            input = input.toString();
          }

          const options = {
            name,
            input,
            minimizerOptions: { ...this.options.minimizerOptions
            },
            minify: this.options.minify
          };

          try {
            output = await (getWorker ? getWorker().transform((0, _serializeJavascript.default)(options)) : (0, _minify.minify)(options));
          } catch (error) {
            compilation.errors.push(HtmlMinimizerPlugin.buildError(error, name, compiler.context));
            return;
          }

          output.source = new RawSource(output.code);
          await cacheItem.storePromise({
            source: output.source
          });
        }

        const newInfo = {
          minimized: true
        };
        const {
          source
        } = output;
        compilation.updateAsset(name, source, newInfo);
      }));
    }

    await Promise.all(scheduledTasks);

    if (initializedWorker) {
      await initializedWorker.end();
    }
  }

  apply(compiler) {
    const pluginName = this.constructor.name;
    const availableNumberOfCores = HtmlMinimizerPlugin.getAvailableNumberOfCores(this.options.parallel);
    compiler.hooks.compilation.tap(pluginName, compilation => {
      compilation.hooks.processAssets.tapPromise({
        name: pluginName,
        stage: compiler.webpack.Compilation.PROCESS_ASSETS_STAGE_OPTIMIZE_SIZE,
        additionalAssets: true
      }, assets => this.optimize(compiler, compilation, assets, {
        availableNumberOfCores
      }));
      compilation.hooks.statsPrinter.tap(pluginName, stats => {
        stats.hooks.print.for("asset.info.minimized").tap("html-minimizer-webpack-plugin", (minimized, {
          green,
          formatFlag
        }) => // eslint-disable-next-line no-undefined
        minimized ? green(formatFlag("minimized")) : undefined);
      });
    });
  }

}

var _default = HtmlMinimizerPlugin;
exports.default = _default;